In 2008, the Times reported, German company Siemens cooperated with the Idaho National Laboratory, allowing it to identify problems in the comany's computer controllers, which are used in Iranian nuclear plants. The laboratory is part of the American Energy Department, which is responsible for nuclear weapons in the US.

The vulnerabilities identified in 2008 were used the following year by Stuxnet.

The Times' report explained how Stuxnet operates. First, it spun Iranian nuclear centrifuges out of control. It would also secretly record the daily routine at the nuclear plant and play back the recording of a regular day to operators at the plant. This way, it would seem that the facility was operating correctly, while the centrifuges were being destroyed.

The Stuxnet virus enters computers through removable drives or through the internet. It then spreads to other computers and any drives that may be plugged into them. The virus searches for computers with Step 7, software that programs Siemens controllers. After a controller is infected, Stuxnet hides itself. After a few days, the virus speeds and slows motors in such a way that could damage them. At the same time, it sends out the false signals described above.

The worm was reportedly only partially successful, delaying Iran's progress but not destroying the nuclear sites.

According to the Times, Stuxnet was developed by the US and Israel, with
help from the Germans and the British, who may not have known the part
they played. Former president George W. Bush reportedly authorized the
program in January 2009, and President Barack Obama, with Israel's
encouragement, ordered that it be accelerated.

A Washington official told the Times that rather than allow Israel to attack Iran, the
US wanted "to put time on the clock...and now, we have a bit more."